Board and setup
The board is half a xiangqi board: thirty-two squares in a 4x8 grid, shown here with the long side horizontal. Unlike xiangqi, pieces sit inside the squares rather than on intersections, and the thirty-two shuffled pieces exactly fill the board, every one face-down.
Colors are not assigned in advance. The first player opens the game by flipping any piece: whatever color comes up is theirs, and the opponent plays the other.
Turns
On your turn, do exactly one of three things: flip any face-down piece, move one of your revealed pieces one square orthogonally onto an empty square, or capture with one of your revealed pieces. A flip reveals the piece to both players, even if it belongs to your opponent. There is no passing.
Capture by rank
Most pieces capture enemy pieces of their own rank or lower by stepping onto an adjacent square. On Mistboard, the order is General > Advisor > Elephant > Chariot > Horse > Soldier. Two exceptions cross the ladder: a soldier can capture the general, and the general cannot capture soldiers.
The cannon sits outside this rank ladder and uses its own capture rule. As a target, though, it still ranks just above the soldier, shown in the dashed slot below. Face-down pieces cannot be captured at all: a piece must be flipped before anyone can take it, which makes every flip next to a strong enemy piece a calculated risk.
The cannon
The cannon ignores rank when it captures. For a capture only, it may travel any distance along a row or column and jump exactly one intervening piece, the screen. It then takes the first piece beyond that screen, and only if that piece is a revealed enemy. If a friendly or face-down piece sits there instead, the line is blocked and the cannon cannot reach past it. The screen itself can be friendly, enemy, or face-down.
A non-capturing cannon move is still just one square orthogonally, like every other piece. Because a cannon needs a screen to capture, it cannot take an adjacent piece. As a target, an adjacent cannon can be taken by a general, advisor, elephant, chariot, or horse, but not by a soldier.
Winning and draws
You win when your opponent has no legal move, usually because every enemy piece is captured, sometimes because they are boxed in. The general is not royal: capturing it is progress, not the win, and play continues until one side is wiped out or stuck.
Mistboard draws a game two ways: 40 plies (single moves) with no flip or capture, or threefold repetition, the same position three times. Either counter resets on any flip or capture, since those cannot be taken back. There is no perpetual-chase rule; over the board, agree the no-progress and repetition limits before you start.
Rules used on Mistboard
There is no single worldwide banqi rules authority. Rank order, cannon captures, repetition, and no-progress limits can differ between clubs, families, and online implementations. Mistboard uses the ladder and screen-jumping cannon described above. For an over-the-board game, agree on those details before the first flip.
Names
暗棋 is Mandarin ànqí, 'dark chess'. The same game is also called 半棋 (half chess) and 翻棋 (flip chess); computer-game literature often calls it Chinese Dark Chess or banqi. Mistboard uses Flip Xiangqi to describe the turn-over-a-tile action. Reveal Xiangqi is the full-board game where hidden pieces reveal after moving, and Fog Chess is the chess variant played under Fog of War.
A sample game
Step through a real game below: MistyBanqi (Strongest) moving first, a human second. The opening flip leaves MistyBanqi playing Red and the human Black. Black wins the opening material (the first eight captures are all Black’s), but Red keeps its elephant, the highest piece left, and grinds out the win. It is a clean illustration that in Flip Xiangqi, rank beats raw material. Tiles flip to their dealt piece the first time they are turned over.
Play on Mistboard
Flip Xiangqi is playable on Mistboard. Play against an engine or challenge a friend. No account required.